DESCRIPTION: (Applicant's Description) This core laboratory is organized to further our collaboration and to ensure all projects use uniform procedures of common assays sharing technical expertise among the projects, conserving resources, and assisting statistical analyses. This core laboratory provides four main functions for various research projects: (1) coordination or radiation equipment usage, (2) the measurements of cell growth and cytotoxicity of cultured cells, (3) tumor development and the measurements of anti-tumor effect, and (4) statistical analyses. For in vitro experiments, cell growth will be measured by colony formation and the induction of apoptosis. Apoptosis will be characterized by morphological changes in nuclear condensation and apoptotic body formation (light microscopy), terminal end-labeling assay for detecting the DNA for cells with free 3'-hydroxyl termini (TUNEL, fluorescence microscopy), DNA content (flow cytometry), and DNA fragmentation (gel electrophoresis). For in vivo experiments, the core laboratory will coordinate the development of tumors in rats (for projects 3 & 4) and in mice (for projects 4 and 5) and intra-tumor infusion of recombinant adenovirus and other agents. Treated tumors will be processed for in vitro colony formation, apoptosis (tissue section by morphology and TUNEL assay), measurements of changes in tumor volume and changes in lifespan. In addition the core laboratory will provide statistical analyses to all project.